Engine heat conservation systems and methods

ABSTRACT

The systems and methods described herein aim to leverage the high temperature of a vehicle&#39;s engine to heat an interior portion of the vehicle. In one embodiment, a heat transfer fluid is pumped through one or more conduits that has a first portion extending through the vehicle&#39;s engine. As the fluid flows through the first portion of conduit, the fluid in the conduit is heated by the engine. The heated fluid flows from the first portion of the conduit to a second portion that is proximate an air handler. The air handler may be configured to blow air over the second portion thereby transferring the heat from the fluid to the air. The heated air may then be provided to the interior portion of the vehicle.

BACKGROUND

Maintaining temperature control within an interior space of a vehicle is typically accomplished while the vehicle's engine is running. In some situations, however, the ability to control the temperature in the interior space of the vehicle is needed when the vehicle is parked, such as for long haul-truckers who sleep in a sleeper portion of the truck or occupy the cabin during government mandated rest periods, as is the case in Class 8 trucks.

One way of maintaining temperature control in the sleeper portion of a parked truck is to idle the engine so that the truck's standard air conditioning and heating system can cool or heat the sleeper portion of the truck. Not only does idling the engine waste energy, but recent legislation has been enacted to limit the amount of time a vehicle's engine may idle.

There is therefore a need for efficient methods and systems for heating or cooling a truck when a vehicle is parked.

SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In accordance with aspects of the present disclosure, a heat conservation system for a vehicle powered by an engine is provided. The heat conservation system may include an air handler comprising a fan and at least one conduit. The at lest one conduit may have a first portion that is located within the engine of the vehicle and a second portion that is located proximate the fan of the air handler. The at least one conduit may be configured to hold a fluid therein. The heat conservation system may further include a pump and an air distribution assembly. The pump may be configured to cause the fluid to flow through the at least one conduit. As the fluid flows through the first portion of the at least one conduit, the engine transfers heat to the fluid. The pump may be caused to be operated when the vehicle engine achieves an engine OFF state. The air distribution assembly may be connected in fluid communication with the air handler. The air handler may be configured to blow air across the second portion of the conduit thereby heating the air. The air distribution assembly may be configured to distribute the heated air to an interior space of the vehicle.

In accordance with aspects of the present disclosure, a method of heating an interior portion of a vehicle having an engine is also provided. The method may include determining whether an ignition switch of the vehicle is in an OFF state, and in response to the ignition switch being in an OFF state, removing heat from the engine. The method further includes providing the heat removed from the engine to the interior portion of the vehicle. The method may further include determining a rate of heat removal from the engine or a temperature of the engine, and in response to the temperature of the engine or the rate of heat removal from the engine being below a threshold value, preventing the removal of heat from the engine.

DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a block diagram of one example of an engine heat conservation system in accordance with aspects of the present disclosure; and

FIG. 2 is a flow diagram of one exemplary method of transferring heat from an engine of a vehicle to an interior space of the vehicle after the engine is turned off in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

The following discussion provides examples of engine heat conservation systems and methods for use in vehicles, such as Class 8 trucks. Generally described, the systems and methods aim to leverage the high temperature of a recently turned off engine to heat an interior portion of the vehicle. As will be explained in more detail below, a heat transfer fluid, such as coolant, water, etc., may be pumped through at least one conduit that extends through the engine. As the heat transfer fluid flows through the at least one conduit in the engine, the heat transfer fluid is heated from the engine. From the engine, the heated fluid is transported to a heat exchanger, such as an air handler. The air handler is configured to blow air over the heated fluid thereby heating the air. The heated air may then be provided to the interior portion of the vehicle.

Although the engine heat conservation systems may be described in reference to heavy duty trucks, such as class 8 vehicles, it should be appreciated that aspects of the present disclosure have wide application, and therefore, may be suitable for use with many types of vehicles, such as passenger vehicles, buses, commercial vehicles, light and medium duty vehicles, etc. Accordingly, the following descriptions and illustrations herein should be considered illustrative in nature, and thus, not limiting the scope of the present disclosure.

It should be appreciated that the engine heat conservation system may be controlled according to various logic and operations that may be performed by conventional electronic components not described herein. The electronic components, which may be grouped in a single location or distributed over a wide area, may include processors, storage devices, input/output circuitry, etc. It will be appreciated by one skilled in the art that the logic described herein may be implemented in a variety of configurations, including but not limited to hardware such as analog circuitry, digital circuitry, processing units, etc., software, and combinations thereof. In circumstances were the components are distributed, the components are accessible to each other via communication links.

While illustrative embodiments are described below, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the claimed subject matter. The illustrative examples provided herein are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Similarly, any steps described herein may be interchangeable with other steps, or combinations of steps, in order to achieve the same or substantially similar result.

Turning now to FIG. 1, there is shown one embodiment of the engine heat conservation system 100 that may be utilized by a vehicle. As best shown in FIG. 1, the engine heat conservation system 100 includes at least one conduit 102 for transporting a heat transfer fluid, such as a coolant, and an air handler 110. The conduit 102 includes a first portion 104 that extends through at least a portion of the engine 106 of the vehicle and a second portion 108 that extends through the air handler 110. As such, the high temperatures of the engine 106 may be utilized to transfer heat from the engine 106 to the heat transfer fluid in the first portion 104 of the conduit 102. In one embodiment, the first portion 104 includes one or more water jackets disposed within the block of the engine 106.

Still referring to FIG. 1, the air handler 110 includes a fan 114 suitably positioned relative to the second portion 108 of the conduit 102 so as to blow air across the second portion 108 of the conduit 102. Heat in the heat transfer fluid in the second portion 108 of the conduit 102 may be transferred to the air via convection as the air is blown across the second portion 108 of the conduit 102.

In one embodiment, the heated air is transferred to the interior space of the vehicle. In that regard, the air handler 110 is connected in fluid communication with an air distribution assembly 120. The air distribution assembly 120 may include a plurality of ducts or the like (not shown) configured to distribute the heated air from the air handler 110 to one or more interior spaces 124 of the vehicle via one or more outlet vents (not shown). As will be clear to those skilled in the art, the ducts, vents, etc. of the air distribution assembly 120 may include some of the ducts, vents, etc. of the standard heating and air conditioning system of the vehicle.

The engine heat conservation system 100 further includes a pump 122 configured to pump the heat transfer fluid through the conduit 102 in a clockwise or counter clockwise direction such that the fluid moves between the engine 106 and the air handler 110. As the heat transfer fluid is circulated through the first portion 104 of the conduit 102, the heat transfer fluid is heated by the residual heat of a recently turned off engine 106 via heat transfer. As the heat transfer fluid that is heated by the engine 106 is circulated from the first portion 104 of the conduit 102 to the second portion 108 of the conduit 102, the heat transfer fluid moves proximate the fan 114 of the air handler 110. As indicated above, the fan 114 is configured to blow air across the second portion 108 of the conduit 102. As the air blows across the second portion 108 of the conduit 102, heat in the heat transfer fluid is transferred to the air thereby heating the air. The heated air is collected by the air distribution assembly 120 for output to the interior space of the vehicle.

The engine heat conservation system 100 further includes a computing device, such as a controller 130. In one embodiment, the controller 130 may receive signals indicative of the ignition switch state, etc. In that regard, the controller 130 may be connected in electrical communication with an engine controller unit (ECU) (not shown) and/or a vehicle ignition switch (not shown). The controller 130 may be directly connected to the ECU or the vehicle ignition switch, or alternatively, the controller 130 may be connected to the ECU or the vehicle ignition switch via a vehicle-wide network, also referred to as a controller area network (CAN). The controller 130 may also be connected in electrical communication with the pump 122, the engine 106, the air handler 110, and/or a power source 132. The power source 132 may be any power source suitable for powering the engine heat conservation system 100, such as a battery or a capacitor. In some embodiments, the power source 132 is the vehicle's standard battery.

A user may control the operation of the engine heat conservation system 100 via an operator interface, such as a control console, provided in an interior space of the vehicle. The operator interface may include a variety of input devices, such as switches, knobs, levers, temperature controls, and the like, coupled in electrical communication with the controller 130. For instance, the input devices may include an ON/OFF switch that operates to activate and deactivate the engine heat conservation system 100. Additionally, the input devices may include a fan selector configured to control the amount of heated air that is blown into the interior space 124 of the vehicle via the air distribution assembly 120. The operator interface may further include a variety of output devices coupled in electrical communication with the controller 130, such as numerical or graphical displays indicating the temperature of the interior space 124 of the vehicle, the temperature of the engine 106, the rate of change of the temperature of the engine 106, and the like.

The engine heat conservation system 100 may further include a plurality of sensors 136, such as temperature sensors, flow rate sensors, or the like, for outputting signals to the controller 130. The plurality of sensors 136 may be coupled directly to the controller 130 or may communicate with the controller 130 via the CAN. In the illustrated embodiment, a temperature sensor 136A is connected in thermal communication to the engine 106 of the vehicle. The temperature sensor 136A measures a temperature of the engine 106 and provides a signal indicative of the measured temperature to the controller 130. Additionally or alternatively, the air handler 110 may include a temperature sensor 136B and/or a flow rate sensor 136C as shown in the illustrated embodiment. The temperature sensor 136B and flow rate sensor 136C may be connected in fluid communication with the heat transfer fluid to measure the temperature and flow rate of the heat transfer fluid, respectively. The temperature sensor 136B and flow rate sensor 136C are configured to generate a signal indicative of the measured temperature or flow rate, respectively, and to provide the corresponding generated signals to the controller 130.

In response to receiving any of the signals from any of the sensors 136 described above, the controller 130 may include suitable logic to compare the received signals to, for example, a threshold value, such as a temperature or rate of change of the temperature of the engine. For example, in response to the measured temperature being less than the threshold value, the controller 130 may be configured to deactivate the engine heat conservation system 130 and/or provide an output signal to an output device of the operator interface.

In some embodiments, the controller 130 may be configured to deactivate the engine heat conservation system 100 in response to the rate of heat removal from the engine or heat transfer fluid being less than a threshold value. In that regard, the controller 130 may be configured to start a timer upon receiving a first signal from the temperature sensor 136A and/or 136B and to stop the timer upon receiving a second signal from the temperature sensor 136A and/or 36B. Using the first and second signals and the time interval between receiving the first and second signals, the controller 130 may include suitable logic to determine a rate of heat removal from the engine or the heat transfer fluid and to compare the rate of heat removal to a threshold value.

To activate the engine heat conservation system 100, the controller 130 may receive one or more signals. For instance, the controller 130 may receive one or more ignition switch state signals indicative of the ignition switch being in an OFF state. In some embodiments, the one or more ignition switch state signals are provided by the ignition switch or the ECU. In one embodiment, the controller 130 receives an ignition switch state signal indicative of the ignition switch transitioning from a first state to a second state, such as an ON state to an OFF state. In an alternative embodiment, the controller 130 receives a first signal indicative of the ignition switch being in an OFF state and a second signal indicative of the vehicle's engine 106 being above a threshold temperature from the temperature sensor 136A. The controller 130 may also receive an activation signal, which may be provided by an input device of the operator interface.

In response to receiving the one or more ignition signals and the activation signal, the controller 130 may generate control signals for output to the pump 122, the fan 114, and/or the like. In that regard, the controller 130 may provide a first control signal to the pump 122 to cause the pump 122 to circulate the heat transfer fluid through the conduit 102 and a second control signal to the air handler 110 to cause the air handler 110 to activate the fan 114.

The engine heat conservation system 100 may be deactivated in response to receiving a signal from an input device of the operator interface, such as by receiving a signal from an ON/OFF switch indicating the switch is in the OFF position, or in response to the temperature of the engine or the heat transfer fluid being below a threshold value. That is, in response to receiving one or more of the signals described above, the controller 130 may be configured to generate control signals to deactivate the engine heat conservation system 100. In some embodiments, the controller 130 may be further configured to activate an auxiliary powered heating system 140 if desired.

It is to be appreciated that the first portion 104 of the conduit may comprise a zigzag, serpentine, or the like configuration through the engine 106 to create a longer path therethrough thereby increasing the amount of heat transferred from the engine 106 to the heat transfer fluid each time the heat transfer fluid cycles through the first portion 104 of the conduit 102. Similarly, the second portion 108 of the conduit 102 may comprise a zigzag, serpentine, or the like configuration through the air handler 110 to create a larger surface area over which the air from the fan 114 is blown, thereby increasing the amount of heat transferred from the heat transfer fluid to the air each time the fluid cycles through the conduit 102.

In an alternative embodiment, the at least one conduit 102 includes a matrix of conduits. For instance, the matrix of conduits may be interconnected via manifolds etc. such that the conduit 102 includes a plurality of rows extending from the first portion 104 to the second portion 108. The heat transfer fluid may flow through each row in the same direction such that the heat transfer fluid flows from the first portion 104 of the conduit 102 into a first manifold connecting the first end of each of the rows and from a second manifold connecting the second end of the rows into the second portion 108 of the conduit 102.

Turning now to FIG. 2, there is shown a flow diagram of one example of a method 200 for heating an interior portion of a vehicle in accordance with aspects of the present disclosure. The method starts a block 202 and proceeds to block 204. At block 204, a controller receives various input signals. In some embodiments, the input signals may include an ignition switch state signal provided by the vehicle's ignition switch or ECU, an engine heat conservation system activation signal provided by the operator interface located in the interior portion of the vehicle, temperature signals, etc.

Next at block 206, a determination is made as to whether the engine heat conservation system has been activated. If the engine heat conservation system has not been activated, then method returns to block 204. If the engine heat conservation system has been activated, then block 206 proceeds to block 208. At block 208, a determination is made as to whether the ignition switch is in the OFF state. If the ignition switch is not in the OFF state but rather in an ON state, the method returns to block 204. If the ignition switch is in the OFF state, block 208 proceeds to block 210.

At block 210, a determination is made as to whether the temperature of the engine is above a threshold temperature. If the temperature of the engine is not above the temperature threshold, then the method returns to block 204. If the temperature of the engine is above the temperature threshold, then block 210 proceeds to block 212. At block 212, the pump 122 and fan of the air handler 110 are activated. That is, the pump 122 is activated to cause heat transfer fluid to flow through the conduit 102, and the fan of the air handler 110 is activated to blow air across the second portion 108 of the conduit 102. Once the pump and fan are activated, sensors 136 in the heat engine conservation system may be monitored at block 214. For instance, the engine's temperature or the heat transfer fluid temperature may be monitored via one or more temperature sensors 136A or 136B.

Next, at block 216, a determination is made as to whether the temperature of the engine or heat transfer fluid is above a threshold temperature. If the temperature of the engine or the heat transfer fluid is above the threshold temperature then the method returns to block 214, otherwise, the method 200 proceeds to block 218 when the pump 122 and/or fan the air handler 110 are deactivated. The method ends at block 220.

The various blocks describing method 200 may be performed sequentially, in parallel, or in a different order than those described herein. For instance, determining whether the ignition switch is in the OFF state at block 208 may occur before, after, or substantially simultaneously with determining if the engine heat conservation system has been activated at block 206 and/or determining if the engine temperature is above a threshold temperature 210. It should also be appreciated that in some implementations one or more of the illustrated blocks may be eliminated, combined or separated into additional blocks. The described and illustrated method 200 may also include various additional blocks not shown.

Various principles, representative embodiments, and modes of operation of the present disclosure have been described in the foregoing description. However, aspects of the present disclosure which are intended to be protected are not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. It will be appreciated that variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present disclosure. Accordingly, it is expressly intended that all such variations, changes, and equivalents fall within the spirit and scope of the claimed subject matter. 

1. A heat conservation system for a vehicle powered by an engine, the heat conservation system comprising: an air handler comprising a fan; at least one conduit having a first portion that is located within the engine of the vehicle and a second portion that is located proximate the fan of the air handler, wherein the at least one conduit is configured to hold a fluid therein; a pump configured to cause the fluid to flow through the at least one conduit, wherein as the fluid flows through the first portion of the at least one conduit the engine transfers heat to the fluid, the pump caused to be operated when the vehicle engine achieves an engine OFF state; and an air distribution assembly connected in fluid communication with the air handler, wherein the air handler is configured to blow air across the second portion of the conduit thereby heating the air, and wherein the air distribution assembly is configured to distribute the heated air to an interior space of the vehicle.
 2. The heat conservation system of claim 1, further comprising a controller coupled in electrical communication with the pump upon one or more operating conditions, the controller configured to provide a signal to the pump, wherein in response to receiving the signal from the controller, the pump causes the fluid to flow through the at least one conduit.
 3. The heat conservation system of claim 2, wherein the controller is configured to generate the signal in response to receiving an ignition state signal indicative of an ignition switch of the vehicle being in an OFF position.
 4. The heat conservation system of claim 2, wherein the one or more operating conditions includes an engine OFF state and a system ON state.
 5. The heat conservation system of claim 4, wherein the system ON state is generated by vehicle user input.
 6. The heat conservation system of claim 2, further comprising a temperature sensor coupled in electrical communication to the controller, wherein the temperature sensor is configured to measure a temperature of the engine and to provide a signal indicative of the measured temperature to the controller.
 7. The heat conservation system of claim 6, wherein the controller is configured to compare the measured temperature to a threshold value, and in response to the measured temperature being below the threshold value, the controller is configured to deactivate the pump and the fan.
 8. The heat conservation system of claim 1 wherein the first portion of the at least one conduit includes a serpentine portion within the engine.
 9. The heat conservation system of claim 1, further comprising an auxiliary powered heating system, wherein the controller is configured provide a signal to the auxiliary powered heating system to initiate the auxiliary powered heating system.
 10. The heat conservation system of claim 1, wherein the fluid is a coolant.
 11. A method of heating an interior portion of a vehicle having an engine, the method comprising: determining whether an ignition switch of the vehicle is in an OFF state; in response to the ignition switch being in an OFF state, removing heat from the engine; providing the heat removed from the engine to the interior portion of the vehicle; determining a rate of heat removal from the engine or a temperature of the engine; and in response to the temperature of the engine or the rate of heat removal from the engine being below a threshold value, preventing the removal of heat from the engine.
 12. The method of claim 11, wherein removing heat from the engine comprises causing a fluid to flow through at least one conduit having a first portion located within the engine thereby transferring the heat from the engine to the fluid.
 13. The method of claim 12, wherein providing the heat removed from the engine to an interior of the vehicle comprises blowing air across a second portion of the conduit thereby heating the air.
 14. The method of claim 11, further comprising determining whether the engine is above a threshold temperature prior to removing heat from the engine, and wherein heat is removed from the engine in response to the engine being above the threshold temperature.
 15. The method of claim 11, wherein determining whether an ignition switch of the vehicle is in an OFF state comprises receiving a signal indicative of the ignition switch transitioning from an ON state to an OFF state.
 16. The method of claim 11, wherein an auxiliary powered heating system is activated in response to the temperature of the engine or the rate of heat removal from the engine being below a threshold value. 